Me with this multiple choice question

The number of revolutions of two pulleys is inversely proportional to their diameters. if a 24-inch diameter pulley making 400 revolutions per minute is belted to an 8-inch diameter pulley, find the number of revolutions per minute of the smaller pulley.

Prove that the value of the expression 7^8–7^7+7^6 is divisible by 43.

Lola says these two expressions have the same value. expression a expression b which explains whether lola is correct?